Mineral - Dioptase
Dioptase
Chemical Properties
Mineral Class
Silicates
Toxicity
none
Formula
CuSiO₃ · H₂O
Unit Cell
a=14.57 c=7.78 Z=18
Physical Properties
Hardness
5
Streak
greenblueblue green
Density
Normal (2-3,5)
Cleavage
Perfect after {10 1 1}
Fracture
conchoidal,
uneven
Tenacity
Brittle
Optical Properties
Color
green
Birefringence
0.052
Luster
Vitreous
Transparency
translucent,
transparent
Pleochroism
Geomineralogical Properties
Crystal System
trigonal
Point Group
rhombohedral - 3
Space Group
R 3 (148)
Habit
prismatic, Rhombohedron
Formation
Oxidation zone of Copper deposits
Paragenesis
Twinning
Rarity
Common
Synonyms
Dioptase
Composition
Elements
Mass
SiO₂
38.93
CuO
49.51
H₂O
11.27
Dana 1892